/*
 * Copyright (c) 2007-2011, Petr Panteleyev
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 *    2. Redistributions in binary form must reproduce the above copyright notice,
 *       this list of conditions and the following disclaimer in the documentation
 *       and/or other materials provided with the distribution.
 *    3. The name of the author may not be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.panteleyev.blogclient;

import java.util.HashMap;

import javax.swing.event.UndoableEditEvent;
import javax.swing.event.UndoableEditListener;
import javax.swing.text.JTextComponent;
import javax.swing.undo.CannotRedoException;
import javax.swing.undo.CannotUndoException;
import javax.swing.undo.UndoManager;

import org.panteleyev.swing.UndoRedoHandler;

/**
 *
 * @author Petr Panteleyev
 */
public class TextUndoManager {
    private UndoRedoHandler _mainFrame;
    private JTextComponent _focused;

    private HashMap<JTextComponent,UndoManager> _managers = new HashMap<>();

    /** Creates a new instance of TextUndoManager */
    public TextUndoManager(UndoRedoHandler frame) {
        _mainFrame = frame;
    }

    public void addComponent(final JTextComponent c) {
        c.addFocusListener(new java.awt.event.FocusAdapter() {
            @Override
            public void focusGained(java.awt.event.FocusEvent evt) {
                _focused = c;
                UndoManager m = _managers.get(_focused);
                if (m != null) {
                    _mainFrame.updateUndoRedo(m.canUndo(), m.canRedo());
                } else {
                    _mainFrame.updateUndoRedo(false, false);
                }
            }
            @Override
            public void focusLost(java.awt.event.FocusEvent evt) {
            }
        });


        final UndoManager m = new UndoManager();
        c.getDocument().addUndoableEditListener(new UndoableEditListener() {
            public void undoableEditHappened(UndoableEditEvent e) {
                m.addEdit(e.getEdit());
                _mainFrame.updateUndoRedo(m.canUndo(), m.canRedo());
            }
        });

        _managers.put(c, m);
    }

    public void undo() {
        if (_focused != null) {
            UndoManager m = _managers.get(_focused);
            if (m != null) {
                try {
                    m.undo();
                    _mainFrame.updateUndoRedo(m.canUndo(), m.canRedo());
                } catch (CannotUndoException e) {
                }
            }
        }
    }

    public void redo() {
        if (_focused != null) {
            UndoManager m = _managers.get(_focused);
            if (m != null) {
                try {
                    m.redo();
                    _mainFrame.updateUndoRedo(m.canUndo(), m.canRedo());
                } catch (CannotRedoException e) {
                }
            }
        }
    }
}
